Transmission jack



y 5, 1953 c. F. HAMER 2,637,449

TRANSMISSION JACK Filed Feb. 6, 1950 2 SHEETS-SHEET l INVENTOR. 32CLARENCE HAMER ATTORNEY y 5, 1953 c. F. HAMER 2,637,449

TRANSMISSION JACK Filed Feb. 6, 1950 2 SHEETSSHEET 2 INVENTOR. CLARENCEE HAMER ATTORNEY Patented May 5, 1953 UNITED STATES PATENT OFFICETRANSMISSION JACK Clarence F. Hamer, Iowa City, Iowa ApplicationFebruary 6, 1950, Serial No. 142,574

4 Claims. 1

The present invention relates to automotive repair equipment, inparticular, to hoists. Hoists for positioning parts of cars from abovehave been in use for many years and are very satisfactory. However, whenit is desired to install or remove heavy parts from the under side ofautomobiles, trucks, or tractors, this can be accomplished to advantagewith the present equipment.

Among the objects of the present invention are the provision of hoistsfor working from below on automotive vehicles; the provision of hoistswhich are simple in design and sufficiently rugged that they will notget out of order in a long life of heavy use; the provision of hoistsfor operation from below a vehicle, which provide for angular adjustmentof the part hoisted in order to effect accurate positioning; and suchfurther objects, advantages, and capabilities as will hereafter appearand as are inherent in the structure disclosed herein and covered by theappended claims.

A preferred form of the present invention is shown in the accompanyingdrawings, in which drawings,

Fig. 1 is an elevation of the present hoist or jack in partiallyelevated position;

Fig. 2 is a plan thereof in lowered position;

Fig. 3 is an end elevation thereof from the left end of Fig. 1;

Fig. 4 is a section of the table on the plane indicated by the line 2-4in Fig. 2; and

Fig. 5 is a detail of the locking mechanism for holding the table inadjusted position.

Reference will now be made in greater detail to the annexed drawings fora more complete description of this invention. In the preferredembodiment shown, this hoist or jack comprises a base equipped withwheels. The base is composed of a U-shaped frame 5 and a frame section lslidable on the frame 6 which is formed of a pair of arms 8, connectedby elbows 9 to the opposite ends of a rod It. Each of elbows 9 hassecured therein a castor II. The frame section I is constituted of a barl2 which has a transverse tubular member 113 secured at each of itsends. These tubular members it are of a size and are so spaced that theyare slidable upon the parallel pair of arms 8 of the frame 6. Thetubular members l3 are likewise provided with castors i l, similar tocasters II. The two pairs of castors, ii and I5, provide for mobility ofthis hoist or jack.

The rod ll} of the U-shaped frame 6 and the bar l2 of the frame sectionI are rigidly mounted at their ends to prevent rotation. A collar I5 issecured to the under side of the bar l2, transversely thereof, at itsmid-point. A second collar it, in alignment with the collar i5, issecured to the under side of the rod Ill. The collar 16 is internallythreaded, and a threaded shaft [1 extends-through the collar IS inscrew-threaded engagement therewith. The shaft ll extends, also, throughthe collar 15 and is provided with a shoulder Hi to abut against the endof the collar Hi remote from the collar It. The shaft I1 is free to turnin the collar [5 but is held against movement therethrough toward thecollar Ii: by the shoulder 13. A second shoulder i9 is secured on theshaft H at the end of the collar l5, nearest to the collar [6. Thisshoulder I9 prevents movement of the shaft if through the collar it awayfrom the collar iii. A hand wheel 26, or other means of turning, isprovided on at least one end of the shaft ll.

Thus, the frame section I is caused to translate forwardly andbackwardly along the arms 8 of the frame 6 upon turning of the shaft ll,since the shaft is threadedly engaged in the collar 16 and isnon-translatably engaged in the collar it).

Two pairs of arms 2i and 22 are pivotally mounted on each of the rod illand the bar i2, respectively, and the ends of each of arms 2i and 22,remote from the rod Hi and the bar 12, are provided with an openingthrough which is placed a bolt 23. The ends of the arms 2! and 22 areaccordingly pivotally connected. A bar 2A is provided with a flangewhich is pivotally mounted on the bolt 23.

Movement of the frame section 7 along the arms 8 by rotation of the handwheel 20 will effect raising and lowering of the pivot 23 and,accordingly, of the bar 24 supported thereby.

In order to control the pivotal position of the bar 22, a collar 26 isprovided, slidable on the bar 24. A lever is mounted at its fulcrum 2?on the arms 2|. One arm 28 of the lever extends upwardly and away fromthe arms 21 and is pivoted to the collar 25. The other arm 29 of thelever extends downwardly from its fulcrum 21. A link 3!], preferably ofadjustable length, is pivoted at its ends to one of the arms 22 and tothe lever arm 29. Adjustment of the length of the link 30 adjusts thepivotal position of the bar 22. The angle between the lever arms 28 and29 and the length thereof is such that, upon raising and lowering of thepivot 23, the pivotal position of the bar 24 remains constant. Whilesuch a constant pivotal adjustment is desirable, it is not essential tothe ultimate broad objective of this invention.

A frame 3| is pivotally supported by the ends of the bar 24 for tiltingsidewise over the bar 23. The frame 3| is constituted of a pair ofplates 32, each pivoted at an end of the bar 2d. The respective ends ofthe plates 32 are connected by facing channels 33. A table 34 isprovided with four wheels 35 at opposite sides of the table, with thewheels movable in the channels 33. The table 34 is thereby movablelengthwise '2 U of the frame 3!. On the under side of the table 36 ismounted a latch bar at for sliding transversely thereof, and a spring 3?is connected at its ends to the table and to the latch bar 36 to slidethe latch bar into latching position, shown in wedged between thechannel 33 and one wheel A toggle 53 is provided to withdraw the latchbar from engaged position. One end .59 or the toggle fit is pivoted tothe latch bar 33. The other end of the toggle 38 is pivoted to a bar il,rigidly mounted with respect to the table 3 3.

One side of the frame St has secured thereto an adjustable length linl;52, the end of which, remote from the frame is secured to the free endof a bar This bar 52} is secured to one of the arms so positioned thatthe free end of this bar is below the pivot 23. By accurate positioningof the free end of the bar 23 with respect to the pivot 23, the angularposition of the frame about the bar 2 may be maintained substantiallyconstant during raising and lowering of the frame 3i by the hand wheel29.

In operation, with the jack in lowered position, the jack is rolledunder the portion of a vehicle which it is desired to remove, the jackis then elevated by turning the hand wheel Upon turning thereof, the rodi 9 approaches the bar l2 and the pairs of arms 25 and elevate the pivot23.

surface of the item to be removed from the vehicle, and that which is toremoved is then disconnected. The table 34 the part supported by thetable are then lowered by turning the hand wheel 20.

To reinstall that which is supported by the table, the operation isreversed. However, during installation, the exact alignment thereof maybe obtained by adjustment of the links so and i2, and of the table inthe frame 35.

While I have described a preferred embodiment of this invention, it isto be understood that the specific structure may be departed fromwithout departing from the spirit of my invention as disclosed hereinand as defined in the appended claims.

Having now described my invention, I claim:

1. A transmission jack comprising a pair of associated frame membersrelatively movable toward and from each other, means for efiectingrelative movement of said associated frame members, pairs of armspivotally connected at their lower ends to said frame members, barsslidable through said frame members, said arms being interconnected attheir other ends by a pivot whereby said pivot moves vertically uponrela tive movement of said frame members, a bar mounted on said pivotperpendicularly thereto, a table mounted on said bar, a bell crank.mounted on one of said pivotally interconnected arm at a point spacedfrom the pivotal mounting of said bar, means connecting one arm of saidbell crank with said a link connecting the other arm of said bell crankwith the other of sai' pivotally interconnected arms at a point spacedfrom said interconnecting pivot, whereby said bar is maintained in suchposition that its longi tudinal axis lies in a plane approximatelyperpendicular to said associated frame members even though it tiltedlongitudinally, supporting means rigidly mounted on one of said arms,and a support pivotally connected to said table and said supportingmeans, whereby angular The angular position of the tablev 3c is thenadjusted to conform to the lower- 4 adjustment of said table in adirection transverse to said bar may be obt ined, said support beingadjustable to provide for leveling said bar.

2. A transmission jack comprising pairs of associated frame membersrelatively movable toward and from each other, means for effectingrelative movement of said frame members, a pair of arms, each pivotallyconnected at its base portion with said frame members, the apicalportions of said arms being interconnected by a pivot, bars connectingthe fran e members for relative sliding motion, a second bar extendinglongitudinally of said first above the latter and having a dependingflange opposite its central portion, said flange being located beyondthe apical portions of said arms and being ,pivotally connected to asupport, and a support mounted for rocking movement of said second barabout the longitudinal axis of said second bar, said support beingrestrained against movement in one direction by a third bar rigidlyconnected to one of said arms.

A transmission jack, twine by claim 2, further characterized a co .4 onsaid bar toward and away i n said pivot, a bell crank mounted on one ranof one of said pairs of arms, a pivot connecting said cranl; with saidcollar, and a link. connec'ed i "all arm of the other pair of arms, at apoi on the last mentioned arm spaced from the aforesaid pivot betweensaid arms and bell cranl; for causing the collar to hold said bar aposition approxii ately to said meinoers when said frame members aremoved toward-and away from each other.

2. A transmission jack comprising pair of relatively movable framemembers, movable toward and away from each other, means for efiectingrelative movement of "Eran e members, a pair of arms pivotally connectedat their lower ends to said frame members, respectively, said arms beinginterconnected at their upper ends by a pivot, whereby pivot movesapproximately vertically upon relative movement of said frame members, abar, forming part of a frame, mounted on said pivot for pivotal movementabout the axis of said pivot, a lever pivoted at an intermediate pointto one of said arms at a point spaced from said pivot, a sleeve slidableon said bar and connecting one end or said lever with said bar, spacedfrom pivot, whereby said frame be turned about said pivot, adjustablelink means pivotally connected with the other end of said lever and withthe other arm at a point spaced from pivot, whereby said bar is held inapproxciately horizontal position when said frame members moved, onerelative to the other, a second bar spaced laterally with respect to thevertical plane 2 first bar and afiixed at one end to move with one ofsaid arms, and a stabilizing linlz connected between the other end ofsaid second bar and the frame, at one side of the of said first bar, tocause turning of said frame about the longitudinal axis of said firstbar.

CLARENCE I-IAIMER.

References Cited in the file of this patent UNITED STATES PATENT$ NumberName Date 1,257,169 Yarbrough Feb. 19, 1918 2,418,443 Wiesner Apr. 1,1947 2,523,734 Stephenson et a1. Sept. 26, 1950

